An evaluation of the Keep on Talking program for maintaining communication skills into old

Communication skills change with age as a result of sensory deficits, memory loss, and increasing word finding difficulties The Keep on Talking program (L. Hickson, H. Barnett, L. Worrall, & E. Yiu, 1994) was developed to assist older people to develop their own strategies for maintaining communication skills into old age. Two hundred and fifty-two healthy older people were recruited from the community and were assessed on a battery of communication assessments on entry to the study and at 1 year after entry. The experimental group (n = 120) participated in the 5-week group Keep on Talking program run by volunteers A further 130 control subjects were assessed only. The short-term effectiveness of the program was evaluated using a short knowledge based and attitudinal questionnaire and qualitative written feedback. At the I-year follow up, subjects were also asked whether they had taken any action as a result of the project. Results concluded that there was a significant difference between the number of correct questionnaire responses on the knowledge based items and the ratings on the attitudinal items pre- and postprogram questionnaire for the experimental subjects. Qualitative written feedback was positive with many participants remarking on the amount of information that they had acquired. Forty-eight experimental and 69 control subjects (n = 117) were assessed I year later, and there was a significant difference between the groups in terms of the number of subjects who reported having taken action as a result of the program. The Keep on Talking program increased knowledge about communication, produced a positive change in attitude toward the importance of communication, and encouraged participants to take action to maintain their communication skills. Maintaining communication skills may prevent social isolation. This simple 5-hour group program has been effective in empowering participants to maintain. their communication skills as they age.

Adjustment to a low-control situation: Reexamining the role of coping responses

The aim of the study was to test a revised conceptualization of the role of coping in adjustment to a low-control stressor-women's adjustment to a failed in vitro fertilization (NF) attempt. Data were collected prior to the IVF treatment (Time I) and twice after the failed NF attempt (1 to 2 weeks after finding out the results, n = 171, and fi weeks later, n = 139). Initial adjustment was assessed at Time I, whereas measures of coping and both self-report and partner ratings of adjustment were obtained at Times ? and 3. As predicted, escapist strategies and problem-management strategies (mainly at Time ?) were associated with poor adjustment, whereas problem-appraisal coping was associated with better adjustment., There was also support for the proposed positive relationship between adjustment and emotional approach coping (on self-report adjustment).

Speciation of arsenic metabolites in the urine of occupational workers and experimental rats using an optimised hydride cold-trapping method

A hydride cold-trapping technique was developed and optimised for the measurement of urinary arsenic metabolites. The analytical precision of the method was found to be 6.1, 4.0 and 4.8% (n = 5) for inorganic arsenic (As-i), monomethylarsonate (MMA) and dimethylarsinate (DMA), respectively, with recoveries close to 100%, The detection limits were 1.0, 1.3 and 3 ng for As-i, MMA and DMA, respectively. The method was then used to analyse urine samples obtained from three groups of workers for occupational exposure in three companies where copper chrome arsenate was used for timber treatment. The results were compared with those for a normal control group of laboratory workers. Arsenic and its metabolites were also measured in experimental rats given 5 mg As kg(-1) body mass by oral gavage in the form of sodium arsenite, calcium arsenite or sodium arsenate. Occupational workers showed a significantly higher excretion of As-i, Up to two fold increases of urinary As-i excretion in rats compared with control rats were also observed in animals dosed with various forms of arsenicals. The method is suitable for the measurement of arsenic metabolites in urine of both humans and experimental animals.

Vaccine-induced Th1-type responses are dominant over Th2-type responses in the short term whereas pre-existing Th2 responses are dominant in the longer term

The effect of adjuvant on induction of human papillomavirus type 16 E7 protein-specific cytotoxic T lymphocytes (CTL) and immunoglobulin G (IgG)(2a) antibody was studied in C57BL/6 J mice immunized with various adjuvants and E7 protein. Quil-A adjuvant, but not complete Freund's adjuvant (CFA) or Algammulin, induced a T-helper 1 (Th1)-type response to E7, which was characterized by CTL activity against a tumour cell line transfected with E7 protein and by E7-specific IgG(2a). All tested adjuvants elicited comparable levels of E7-specific IgG(1). The longest duration and greatest magnitude of CTL response was seen following two immunizations with the highest dose of E7 and Quil-A. Simultaneous immunization with a Th1 and a T helper 2 (Th2)-promoting adjuvant gave a Th1-type response. However, E7 and Quil-A were unable to induce a Th1-type response (as measured by the inability to generate anti-E7 IgG(2a) antibody) in animals with a pre-existing Th2-type response to E7. These results suggest that saponin adjuvants may be suitable for immunotherapy in humans where a Th1-type response is sought, provided that there is no pre existing Th2-type response to the antigen.

Experimental and theoretical investigations of adsorption hysteresis and criticality in MCM-41: Studies with O-2, Ar, and CO2

MCM-41 materials of six different pore diameters were prepared and characterized using X-ray diffraction, transmission electron microscopy, helium pycnometry, small-angle neutron scattering, and gas adsorption (argon at 77.4 and 87.4 K, nitrogen and oxygen at 77.4 K, and carbon dioxide at 194.6 K). A recent molecular continuum model of the authors, previously used for adsorption of nitrogen at 77.4 K, was applied here for adsorption of argon, oxygen, and carbon dioxide. While model predictions of single-pore adsorption isotherms for argon and oxygen are in satisfactory agreement with experimental data, significant deviation was found for carbon dioxide, most likely due to its high quadrupole moment. Predictions of critical pore diameter, below which reversible condensation occurs: were possible by the model and found to be consistent with experimental estimates, for the adsorption of the various gases. On the other hand, existing models such as the Barrett-Joyner-Halenda (BJH), Saito-Foley, and Dubinin-Astakhov models were found to be inadequate, either predicting an incorrect pore diameter or not correlating the isotherms adequately. The wall structure of MCM-41 appears to be close to that of amorphous silica, as inferred from our skeletal density measurements.

Experimental control of single-mode laser chaos by using continuous, time-delayed feedback

Control of chaos in the single-mode optically pumped far-infrared (NH3)-N-15 laser is experimentally demonstrated using continuous time-delay control. Both the Lorenz spiral chaos and the detuned period-doubling chaos exhibited by the laser have been controlled. While the laser is in the Lorenz spiral chaos regime the chaos has been controlled both such that the laser output is cw, with corrections of only a fraction of a percent necessary to keep it there, and to period one. The laser has also been controlled while in the period-doubling chaos regime, to both the period-one and -two states.

An experimental study of the effects of work stress, work control, and task information on adjustment

The present study was designed to examine the main and interactive effects of task demands, work control, and task information on levels of adjustment. Task demands, work control, and task information were manipulated in an experimental setting where participants completed a letter-sorting activity (N = 128). Indicators of adjustment included measures of positive mood, participants' perceptions of task performance, and task satisfaction. Results of the present study provided some support for the main effects of objective task demands, work control, and task information on levels of adjustment. At the subjective level of analysis, there was some evidence to suggest that work control and task information interacted in their effects on levels of adjustment. There was minimal support for the proposal that work control and task information would buffer the negative effects of task demands on adjustment. There was, however, some evidence to suggest that the stress-buffering role of subjective work control was more marked at high, rather than low, levels of subjective task information.

Studies of evolutionary temperature adaptation: Muscle function and locomotor performance in Antarctic fish

1, Studies of evolutionary temperature adaptation of muscle and locomotor performance in fish are reviewed with a focus on the Antarctic fauna living at subzero temperatures. 2. Only limited data are available to compare the sustained and burst swimming kinematics and performance of Antarctic, temperate and tropical species. Available data indicate that low temperatures limit maximum swimming performance and this is especially evident in fish larvae. 3, In a recent study, muscle performance in the Antarctic rock cod Notothenia coriiceps at 0 degrees C was found to be sufficient to produce maximum velocities during burst swimming that were similar to those seen in the sculpin Myoxocephalus scorpius at 10 degrees C, indicating temperature compensation of muscle and locomotor performance in the Antarctic fish. However, at 15 degrees C, sculpin produce maximum swimming velocities greater than N, coriiceps at 0 degrees C, 4, It is recommended that strict hypothesis-driven investigations using ecologically relevant measures of performance are undertaken to study temperature adaptation in Antarctic fish, Recent detailed phylogenetic analyses of the Antarctic fish fauna and their temperate relatives will allow a stronger experimental approach by helping to separate what is due to adaptation to the cold and what is due to phylogeny alone.

Likelihood-based estimation of the regression model with scrambled responses

A significant problem in the collection of responses to potentially sensitive questions, such as relating to illegal, immoral or embarrassing activities, is non-sampling error due to refusal to respond or false responses. Eichhorn & Hayre (1983) suggested the use of scrambled responses to reduce this form of bias. This paper considers a linear regression model in which the dependent variable is unobserved but for which the sum or product with a scrambling random variable of known distribution, is known. The performance of two likelihood-based estimators is investigated, namely of a Bayesian estimator achieved through a Markov chain Monte Carlo (MCMC) sampling scheme, and a classical maximum-likelihood estimator. These two estimators and an estimator suggested by Singh, Joarder & King (1996) are compared. Monte Carlo results show that the Bayesian estimator outperforms the classical estimators in almost all cases, and the relative performance of the Bayesian estimator improves as the responses become more scrambled.

Experimental study of phase equilibria in the system PbO-ZnO-SiO2

An experimental study on the ternary system PbO-ZnO-SiO2, in air by high-temperature equilibration and quenching techniques followed by electron probe X-ray microanalysis was carried out as part of the wider research program on the six-component system PbO-ZnO-SiO2-CaO-FeO-Fe2O3, which combines experimental and thermodynamic computer modeling techniques to characterize zinc and lead industrial slags. Liquidus and solidus data were reported for all primary phase fields in the system PbO-ZnO-SiO2 in the temperature range 640 degrees C to 1400 degrees C (913 to 1673 K).

Histologic and immunohistochemical responses after aortic valve allografts in the rat

Background. Human aortic valve allografts elicit a cellular and humoral immune response. It is not clear whether this is important in promoting valve damage. We investigated the changes in morphology, cell populations, and major histocompatibility complex antigen distribution in the rat aortic valve allograft. Methods. Fresh heart valves from Lewis rats were transplanted into the abdominal aorta of DA rats. Valves from allografted, isografted, and presensitized recipient rats were examined serially with standard morphologic and immunohistochemical techniques. Results. In comparison with isografts, the allografts were infiltrated and thickened by increased numbers of CD4(+) and CD8(+) lymphocytes, macrophages, and fibroblasts. Thickening of the valve wall and leaflet and the density of the cellular infiltrate was particularly evident after presensitization. Endothelial cells were frequently absent in presensitized allografts whereas isografts had intact endothelium. Cellular major histocompatibility complex class I and II antigens in the allograft were substantially increased. A long-term allograft showed dense fibrosis and disruption of the media with scattered persisting donor cells. Conclusions. The changes in these aortic valve allograft experiments are consistent with an allograft immune response and confirm that the response can damage aortic valve allograft tissue. (C) 1998 by The Society of Thoracic Surgeons.

Associative priming in color naming: Interference and facilitation

In Experiment 1, color-naming interference for target stimuli following associated primes was greater in a group making a lexical decision to the prime than in a group reading the prime silently. High-frequency targets were responded to more quickly than low-frequency targets. In Experiment 2, with subjects naming the prime, there was evidence of associative interference when the prime and the target were grouped temporally but not when the intertrial interval was comparable with the prime-target interval. Associative primes presented at a short (120-msec) prime-target stimulus onset asynchrony facilitated color naming in Experiment 3. Taken together, the results suggest that the effect of faster processing of the base word in a color-naming task is facilitatory and that color-naming priming interference arises when associative prime processing increases conflict between word and color responses by enhancing phonological or articulatory activation of the base word.

Cytomegalovirus evasion of natural killer cell responses

Natural killer (NK) cells are an important component of the innate cellular immune system. They are particularly important during the early immune responses following virus infection, prior to the induction of cytotoxic T cells (CTL). Unlike CTL, which recognize specific peptides displayed on the surface of cells by class I MHC, NK cells respond to aberrant expression of cell surface molecules, in particular class I MHC, in a non-specific manner. Thus, cells expressing low levels of surface class I MHC are susceptible to recognition by NK cells, with concomitant triggering of cytolytic and cytokine-mediated responses. Many viruses, including the cytomegaloviruses, downregulate cell surface MHC class I: this is likely to provide protection against CTL-mediated clearance of infected cells, but may also render infected cells sensitive to NK-cell attack. This review focuses upon cytomegalovirus-encoded proteins that are believed to promote evasion of NK-cell-mediated immunity. The class I MHC homologues, encoded by all cytomegaloviruses characterised to date, have been implicated as molecular 'decoys', which may mimic the ability of cellular MHC class I to inhibit NK-cell functions. Results from studies in vitro are not uniform, but in general they support the proposal that the class I homologues engage inhibitory receptors from NK cells and other cell types that normally interact with cellular class I. Consistent with this, in vivo studies of murine cytomegalovirus indicate that the class I homologue is required for efficient evasion of NK-cell-mediated clearance. Recently a second murine cytomegalovirus protein, a C-C chemokine homologue, has been implicated as promoting evasion of NK and T-cell-mediated clearance in vivo.

Relationships between movement initiation times and movement-related cortical potentials in Parkinson's disease

Movement-related cortical potentials recorded from the scalp reveal increasing cortical activity occurring prior to voluntary movement. Studies of set-related cortical activity recorded from single neurones within premotor and supplementary motor areas in monkeys suggest that such premovement activity may act to prime activity of appropriate motor units in readiness to move, thereby facilitating the movement response. Such a role of early stage premovement activity in movement-related cortical potentials was investigated by examining the relationship between premovement cortical activity and movement initiation or reaction times. Parkinson's disease and control subjects performed a simple button-pressing reaction time task and individual movement-related potentials were averaged for responses with short compared with long reaction times. For Parkinson's disease subjects but not for the control subjects, early stage premovement cortical activity was significantly increased in amplitude for faster reaction times, indicating that there is indeed a relationship between premovement cortical activity amplitude and movement initiation or reaction times. In support of studies of set-related cortical activity in monkeys, it is therefore suggested that early stage premovement activity reflects the priming of appropriate motor units of primary motor cortex, thereby reducing movement initiation or reaction times. (C) 1999 Elsevier Science B.V. All rights reserved.